Recent budget talks between the White House and Congress shows that President Trump puts a high value on funding the construction of a border wall. Crucial to this debate is how much a border wall will cost to construct and maintain. Center for Immigration Studies (CIS) published a brief report purporting to show that building a wall along the southern border would pay for itself if it keeps out only 160,000 to 200,000 border crossers over the next decade. That means the border wall would only have to deter about 9 to 12 percent of all illegal border crossers who would have successfully made it into the United States during that period. The report uses a variety of assumptions that unrealistically lower the cost of the wall as well as inflate the fiscal cost of border crossers.
We used more recent and precise data to update CIS’s analysis without altering its methodology. Simply using newer numbers—with no changes to the report’s unrealistic underlying assumptions—proves that the border wall cannot pay for itself. Despite fanciful promises to the contrary, a border wall is too expensive and will deter too few illegal immigrants to pay for itself—even under assumptions that are extremely generous to those who support a wall.
Updating CIS’ Analysis
The first update was to factor in a more recent estimate of the cost of a border wall. The CIS study chose to rely on a statement made by Senator Majority Leader Mitch McConnell (R-KY) rather than any actual cost estimate. We used an official estimate from the Department of Homeland Security (DHS) issued after the majority leader’s comment. This placed the cost of building a 1,250-mile border wall at $21.6 billion, or $17,280,000 per mile, that includes all costs such as the condemnation of private property through eminent domain. We also include the yearly maintenance costs.
The second is that we adjust CIS’ fiscal cost estimate by controlling for the age of the border crossers. The National Academy of Sciences (NAS) fiscal cost estimates show that the immigrant age of arrival is vital for estimating their fiscal impact. CIS used the 2010 education level of Mexican illegal immigrants as a proxy for the education level of all future border crossers. We used the March CPS to adjust for this by assuming that the education of future illegal immigrants will be more similar to those arriving in 2015 than 2010. We further divided up the illegal border crossers by age and education to get a more accurate view of their potential fiscal impact.